[ 
https://issues.apache.org/jira/browse/IMPALA-7867?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16739786#comment-16739786
 ] 

ASF subversion and git services commented on IMPALA-7867:
---------------------------------------------------------

Commit 049e1056f8d772c55274a54ff99e2cf44b82fa56 in impala's branch 
refs/heads/master from paul-rogers
[ https://git-wip-us.apache.org/repos/asf?p=impala.git;h=049e105 ]

IMPALA-7867 (Part 4): Collection cleanup in catalog

Continues the collection clean work to:

* Use collection interfaces for variable and function argument
  declarations,
* Replace generic Guava newArrayList(), etc. calls with the direct use
  of the Java collection classes,
* Clean up unused imports and add override annotations.

This patch focuses on the catalog module and its tests.

Tests: this is purely a code change, no functional change. Reran
existing tests.

Change-Id: Ic83425201c90966aae4c280d94cf1b427b3d71d1
Reviewed-on: http://gerrit.cloudera.org:8080/12131
Reviewed-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com>


> Expose collection interfaces, not implementations
> -------------------------------------------------
>
>                 Key: IMPALA-7867
>                 URL: https://issues.apache.org/jira/browse/IMPALA-7867
>             Project: IMPALA
>          Issue Type: Improvement
>          Components: Frontend
>    Affects Versions: Impala 3.0
>            Reporter: Paul Rogers
>            Assignee: Paul Rogers
>            Priority: Minor
>
> When using Java collections, a common Java best practice is to expose the 
> collection interface, but hide the implementation choice. This pattern allows 
> us to start with a generic implementation (an {{ArrayList}}, say), but evolve 
> to a more specific implementation to achieve certain goals (a {{LinkedList}} 
> or {{ImmutableList}}, say.)
> For whatever reason, the Impala FE code exposes {{ArrayList}}, {{HashMap}} 
> and other implementation choices as variable types and in method signatures.
> This ticket tracks a gradual process of revising the declarations and 
> signatures to use the interfaces {{List}} instead of the implementation 
> {{ArrayList}}.
> Also, the FE code appears to predate Java 7, so that declarations of lists 
> tend to be in one of two forms (with or without Guava):
> {code:java}
> foo1 = new ArrayList<Bar>();
> foo2 = Lists.newArrayList();
> {code}
> Since Java 7, the preferred form is:
> {code:java}
> foo = new ArrayList<>();
> {code}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org
For additional commands, e-mail: issues-all-h...@impala.apache.org

Reply via email to